Behringer MDX1400 Anticipated Compression, Tab .1 Initial settings for the De-Esser functions

AUTOCOM PRO MDX1400

Control	Setting
SC EXT switch	IN
SC MON switch	OUT
INTERACTIVE switch	OFF
SC FILTER switch	OUT
THRESHOLD control	+20 dB
RATIO control	1:4
AUTO switch	OUT
ATTACK control	0,5 ms
RELEASE control	200 ms
OUTPUT control	0 dB

Tab. 5.1: Initial settings for the De-Esser functions

5.2.2 Frequency Selective Filtering Of Unwanted Signals

Based on the set-up described in the de-esser section, the unit may also be used to eliminate rumble, hum and equipment noise (air-conditioning systems, camera noise etc.). Using the SC MON switch, adjust the frequencies of the equalizer to match the unwanted frequencies and use a peak filter with a high slope. Take care to decrease the amplitudes of the unrequired frequencies. Proceed now as described in the previous chapter 5.2.1. This will result in compression of the selected frequencies and thus a decrease in the gain of the program material.

5.2.3 Suppressing Instruments During Recording

Another function of the BEHRINGER AUTOCOM PRO allows helpful correction of previously recorded material. If, for example, an excessively loud bass drum needs to be suppressed, reduce all the equalizers frequency bands above 150 Hz. This setting causes frequency specific compression, which reacts as soon as increased energy is detected in this band. By increasing the threshold level, the compression can be made to react only to loud pedal or stick actions. Generally, it can be said that relatively high threshold settings prevent the overall sound from being impaired and lead to the compression of solo instruments or very loud sounds.

5.2.4 Emphasizing Musical Instruments During Recording

On the other hand, you can use the BEHRINGER AUTOCOM PRO to bring out an instrument solo or a lead vocal in a cluttered mix. Using the SC MON switch, match the frequencies of the equalizer to the frequencies of the instruments to be emphasized and for this it is best to use a notch filter with a high slope.

Please make sure that in this application, you only reduce the amplitude of the selected frequencies. The compression results in a subjective decrease in the volume of the overall program material. Only the selected frequencies coming from the equalizer remain uncompressed and are therefore perceived as being louder. This inverse type of compression also helps to emphasize instruments during low level passages, so that they become more pronounced.

5.3 Anticipated Compression

If you feed the audio signal directly into the SC RETURN input and send the audio signal through a delay before the audio input, the BEHRINGER AUTOCOM PRO can anticipate the need for gain change. With experimentation, the effect can create a “zero” attack time at a given frequency. Additional delay beyond this “zero” attack time will produce a special sound effect, similar to the dynamic envelope inversion you may already be familiar with from reverse tape playback.

5. EXTERNAL SIDECHAIN APPLICATIONS 21